- A new study from Kodagu in Karnataka examines civet latrines in three habitats of varying openness and challenges the popular notion that civets are open defecators.
- Conducted during the ripening period of civets’ preferred fruits, the study finds that the number of scats increased with canopy cover and that more scats are sampled above the ground than on it.
- Despite doubts about civets’ efficiency as seed dispersers, researchers agree on their crucial role in propagating plants in tropical regions experiencing defaunation.
Science has long been fascinated by civets and their faecal matters, primarily because they are one of the most efficient seed dispersers in the natural world. A new study from Kodagu in Karnataka examines civet latrines in three different habitats — coffee plantations, sacred groves, and home gardens — and challenges the commonly held belief about civets as open defecators.
Studies provide evidence of palm civet’s (Paradoxurus hermaphroditus) ability to disperse seeds — an earlier study from Myanmar has found that the species can take between eight and 21 species of fruit per two-month period throughout the year, whereas the new study has found 4,234 seeds in 105 scat samples studied.
Civets are the OG waste-to-wealth creators, using their seed-filled droppings that visually resemble nutrition bars, to enrich the natural flora. They could sue humans for copyright infringement for harvesting their unique poop to brew expensive coffee sold as Kopi Luwak to the wealthy.
The latest study was conducted in the three diverse habitats of palm civet during the fruit ripening period of its two preferred fruits — coffee cherry and Caryota urens (Bastard sago palm); while sacred groves are largely closed habitats, coffee plantations provide a partially closed microhabitat and home gardens are relatively open habitats. A total of 105 scat samples were collected — 55 from coffee plantations, 45 from sacred groves and five from home gardens.
No to open defecation
Researchers found that the number of scats increased with canopy cover and that more scats were sampled off the ground than on it. The paper notes that these findings contradict the popularly held belief that civets defecate more in open areas. Moreover, the prevalence of civet latrines off the ground indicates the need for more critical analyses of their role as efficient seed dispersal agents in different contexts.
Civets are largely frugivores in the order Carnivora, performing a crucial service to plants that are dependent on animals for seed dispersal. However, they must disperse seeds in favourable microclimates with minimal disturbances by seed predators or herbivores, among others. This makes their defecation habits critical for assessing their efficiency as dispersal agents and predicting the fate of animal-dispersed seeds, the paper notes.
Defecation behaviour tells us where the animals move the seeds to. Though they are frugivores, their defecation behaviour is something like other carnivores. They prefer open places for defecation and often have a specific spot for routine latrine,” explains assistant professor at the Central University of Kerala and the lead author of the study, Palatty Allesh Sinu.
Literature suggests that palm civets choose open (non-shady) places for defecation. He says that if that were true, then plants that are non-tolerant of shades (or pioneer plants) could benefit from civets more than those that are not. However, the study observed that civets were in fact moving seeds to shady areas, contradicting the general belief based on previous literature that they are open defecators. This finding also highlights their importance as dispersal agents for climax plants that are tolerant of shade. “The number of civet scats was higher in sacred groves (which are closed forests) than in home gardens, a relatively open habitat,” Sinu adds.
Night party on the logs
Another finding, consistent with earlier studies on palm civets, is their preference for defecating on elevated surfaces slightly above the ground. This, Sinu says, “puts another challenge for the seeds unless they are pushed down by dung beetles, the secondary seed dispersal agents.” An earlier study by Chakravarthy and Ratnam in 2015 had found a majority of seeds to be dispersed on fallen logs and canopy branches.
Director of Wildlife Biology and Conservation at National Centre for Biological Sciences (NCBS) in Bengaluru, Jayashree Ratnam who conducted the 2015 study says that the fate of the seeds dispersed by civets on elevated surfaces remain highly stochastic (variable). In her study, conducted in a tropical rainforest, she observed scats on logs which tend to disintegrate. They provide nutrients and other elements that support the germination of the seeds in them. “So, logs may not be a bad place for a seed to germinate. But this is quite variable. A log may not be a very sunny or a very desiccating place. So, the bottom line is, what is going to happen to the fate of those seeds remains highly stochastic,” she says.
Researchers also agree that home gardens may not be ideal environments for seed germination via civet latrines. In the present study, very few scats were collected from home gardens, most of which were found off the ground, significantly reducing their potential for germination, according to the researchers.
“The number of scats encountered in the forests and coffee plantations were the same. I have no clue why the number of scat in the home gardens was less. Though we have replicated the study sufficiently, there is a possibility that we miss their paths in our survey. Poaching of civets can’t be ruled out as well,” Sinu shares.
Despite the study findings, researchers maintain that civets continue to be important seed-dispersal agents in the tropics that are seeing increased defaunation or removal of large vertebrates from their habitats either due to climate change or anthropogenic pressures, says Sinu. Civets’ nocturnal behaviour reduces competition from daytime frugivores, and like bats, they are less wary around humans, facilitating seed movement. Ratnam concurs, highlighting civets as rare and significant species. “Globally, many key seed dispersers are disappearing. In such times, civets quietly perform a vital ecological function,” she asserts.
Banner image: An Asian palm civet in Thailand. A new study busts the popularly held notion that civets are open defecators. Image by Bernard Dupont from France via Wikimedia Commons (CC BY-SA 2.0).
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